1. Field of the Invention
The present invention relates gnerally to an apparatus for assembling a pair of fastener elements of a garment fastener, such as a button, a snap button, a rivet or an ornament, with a garment fabric disposed between the two fastener elements. More particularly, it relates to a fastener-assembling apparatus having an improved drive mechanism for reciprocating an optical position indicator for indicating a position on the garment fabric where the two fastener elements are to be attached.
2. Prior Art
There have been proposed various fastener-assembling apparatus of the type including a pair of upper and lower holder units for holding respectively thereon a pair of fastener elements, a punch vertically reciprocable toward and away from a die to clinch the two fastener elements with a garment fabric disposed therebetween, and an optical position indicator for indicating a position on the garment fabric where the two fastener elements are to be attached.
The position indicator is driven by a drive mechanism which is structurally and functionally independent from a punch-driving mechanism. The indicator-driving mechanism is so constructed as to reciprocate the position indicator between an advanced indicating position and a retracted standby position in such a manner that an advancing motion of the position indicator begins subsequent to arrival of the punch at its uppermost standby position, and a retracting motion of the position indicator begins prior to departure of the punch from the uppermost standby position.
With this timed operational relation between the punch and the position indicator, it is difficult to operate the fastener-assembling apparatus at a high speed. Furthermore, the position indicator is likely to interfere with the upper holder unit while the upper unit is reciprocating in unison with the punch. Accordingly, a tedious and time-consuming adjustment is necessary to accurately time the reciprocation of the position indicator with the vertical reciprocation of the punch.